Studio: Add zip files support for blueprints

[katinthehatsite]

Related issues

Fixes STU-1495

How AI was used in this PR

It was used to identify the fix but I questioned its fix and then it improved the fix.

Proposed Changes

This PR ensures that you can create a site when using not only .json format for blueprints but also .zip files that contain blueprints.

Testing Instructions

• Pull the changes from this branch
• Start Studio
• Download a sample blueprint such as WordPress blueprints trunk blueprints-news-spiel.zip
• Add a new site by using this blueprint
• Confirm that the site creation succeeds
• Confirm that the blueprint was applied successfully

Pre-merge Checklist

• Have you checked for TypeScript, React or other console errors?

[wpmobilebot]

📊 Performance Test Results

Comparing 111b02e vs trunk

app-size

Metric	trunk	111b02e	Diff	Change
App Size (Mac)	1490.94 MB	1490.96 MB	+0.01 MB	⚪ 0.0%

site-editor

Metric	trunk	111b02e	Diff	Change
load	1892 ms	1896 ms	+4 ms	⚪ 0.0%

site-startup

Metric	trunk	111b02e	Diff	Change
siteCreation	10129 ms	8122 ms	2007 ms	🟢 -19.8%
siteStartup	5946 ms	4949 ms	997 ms	🟢 -16.8%

---

Results are median values from multiple test runs.

Legend: 🟢 Improvement (faster) | 🔴 Regression (slower) | ⚪ No change (<50ms diff)

[nightnei]

Works well, as expected 👍

[nightnei]

Thanks Kat, LGTM and I tested one more time - works as expected 👍